


Perspicacity

by Starrie_Wolf



Series: City of Ruins [4]
Category: Mortal Instruments Series - Cassandra Clare
Genre: A television is a very useful tool, BAMF Alec, Canon-Typical Violence, Description of a naked woman by a homosexual, Established Relationship, Future Fic, Gen, In case you didn't know what a lamia is, Lamia, M/M, Mission Fic, Monster of the Week, Mythical Beings & Creatures, Naked woman who eats children, No Gore, Post-Series, The only time sexuality actually matters
Language: English
Status: Completed
Published: 2015-09-09
Updated: 2015-09-09
Packaged: 2018-04-18 06:46:05
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,054
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4696145
Author URL: https://archiveofourown.org/users/Starrie_Wolf/pseuds/Starrie_Wolf
Summary: <blockquote class="userstuff">
              <p>Magnus' library contained tomes all the way back, even some from the lost Library of Alexandria, but that wasn't the reason why Alec was there.</p><p>  <i>I need to know about lamiae. I need to stop it.</i></p><p>It was all about the intent.</p>
            </blockquote>





	Perspicacity

**Author's Note:**

  * For [boywonder](https://archiveofourown.org/users/boywonder/gifts).



> In case you didn't pay attention to the Additional Tags, this story contains a lamia, which means it comes with all the appropriate **warnings** \- a naked woman from the waist up with the lower half of a snake, a brief mention of dead children, mentions of succubus-like seduction magic occurring offscreen, and the monster (who happens to look like a human woman, in case this part bears repetition) dies at the end. If any of these distresses you, please don't read it.
> 
> To boywonder, for whom this fic is actually written: I double-checked your letter, and none of the above appears in your dislikes. You asked for monsters, some kind of character development (a little difficult in something so short I'm afraid), and "a serious fic of them loving each other" without silly fluff. I hope I've managed to deliver.

There were certainly many perks to dating a 900-year-old warlock, decided Alec. A faint grin tugged helplessly at his lips at the sight of the wall-to-floor bookshelves, fairly groaning under the weight of the tomes resting upon them. Apparently, Magnus _did_ own the entire apartment building, not just the loft, and his library ought to be nominated as a state treasure. He’d heard that Magnus had even rescued a few of the rare tomes from the Library of Alexandria before its destruction, and Alec had been _dying_ to get a peek at them.

Not that he was dating Magnus solely for his books, but it was just – nice. And useful, in times like this, when he needed to do some research and the Institute library failed him.

Like the warlock himself, the library was seemingly a haphazard mess at first sight, the books stacked with no apparent order to them. Alec rested a hand on the bookshelf directly in front of him, tracing the veined wood absently while he examined its contents. At his eye level was a copy of Shakespeare’s First Folio, next to a treatise on the proper usage and management of poultices that must have dated from the Middle Ages, and the shelf immediately above boasted a collection of colourful travel guides around the world.

He’d never be able to find what he was looking for the normal way.

Alec took a calming breath and closed his eyes, this time reaching out not with his hand, but with his heart.

_I need to know about lamiae._

He didn’t hold the thought as mere words, but as a series of images flashing across his mind’s eye – tiny piles of bones picked clean, arrayed neatly on the rocks like sacrificial offerings, that one caretaker still in a coma in the hospital – as though he was viewing one of those _television_ things Magnus adored so much, but caught in an undercurrent of anxiety and agitation, a tumult of emotions bleeding into a torrent of _wanthelpprotect –_

_I need to stop it._

Intent, Magnus had once told him. It was all about the intent.

His fingers bumped up against smooth worn leather, and startled, Alec opened his eyes. He was standing in front of a completely different bookshelf than before, though he didn’t remember moving – or perhaps the books had merely rearranged themselves while he wasn’t looking? – with a single book resting on the shelf at his eye level.

The tome was old, he could see that at once, all embossed lettering and hand-sewn parchment. Alec carefully cracked it open, and the illustration of a giant serpent with the torso of a woman leapt out of the page at him. He’d found it.

Flipping to the next page, Alec began to read.

~*~*~*~*~

Arms slid around his waist, and Alec _jumped_.

Magnus casually tilted his head to let the knife fly harmlessly past his ear, and then plucked the quivering blade from the bookshelf behind him where it had embedded itself, offering it back to Alec hilt-first.

“Sorry,” Alec muttered, toying with his returned knife.

Magnus shrugged, and he didn’t look the slightest bit concerned. Alec swallowed and told himself to _drop it_ , because if the warlock wasn’t the sort of person who’d put up with a situation that bothered him. If Magnus didn’t like it, he’d have told Alec so.

“I’ve been meaning to redecorate anyway. Beech wood would look better than oak, give the library a splash of colour. What do you think?”

“Um,” Alec said eloquently. It’d taken him _months_ to figure out that Magnus wasn’t humouring him or just talking out loud to himself, he genuinely wanted Alec’s opinion on these matters. Nobody’d ever wanted his opinions before. “I think maple would be better if you’re going for rich colours,” he managed to reply, and was proud of the way his voice didn’t even lilt into a question at the end.

It was worth every bit of effort to see the way Magnus beamed back at him. “Maple it shall be, then.” He nodded to himself, and then turned back to Alec. “Hungry?”

Alec blinked. It wasn’t a question he was expecting, since – “Didn’t we just have breakfast?”

Magnus simply looked fondly exasperated. “Alexander dear, you’ve been in here for six hours; come out and eat something. You can bring the book.”

His cheeks pinked as he obediently followed Magnus up to the loft area. Six… hours? Had it really been that long?

The table was already set for two, laden with platters of cold cuts and steaming dishes of pasta. Alec’s blush deepened as his stomach gave an involuntary growl at the tantalising smell, letting him know that yes, it really had been that long since his last meal. He carefully set the tome on magical creatures on the couch, and slid into his usual seat at the table.

~*~*~*~*~

The meal was probably delicious, but Alec had no memory of what his food tasted like. Magnus was sprawled over the couch, idly flipping through the television channels, while Alec made a beeline for the tome. The warlock’s eyes hadn’t so much as flickered down to the book in his hands, but there was no doubt Magnus knew exactly what Alec was reading.

After all, the spate of lamia attacks was just about the only thing everyone was talking about, from the Shadowhunters to the Downworlders. Eight children had already died, all of them below the age of five, and all efforts to hunt down the perpetuator had failed so far. Grainy footage from a serendipitously-positioned security camera confirmed that she was at least three metres in length, but the quality of the video had been so bad that they couldn’t even identify the patterning on her scales.

She was a fully-matured lamia, that much had to be certain, given the trail of enthralled males – and the occasional female – that she left in her wake. If it wasn’t for all the dead children, they would have suspected her cousin the succubus.

Some kind of preppy pop song started up on the television, but he tuned it out. Magnus had just spent the past three days warding the New York Institute, where every single Downworlder child was now sequestered, to Hell and back. He had to be utterly exhausted by now. If the warlock wanted to listen to strange mundane music, he’d certainly earned that.

Alec flipped another page, skimming through the anecdotes. Cold-blooded… nocturnal… might be venomous depending on the species of snake. Nothing he didn’t already know. Every single cave in New York had been checked and double-checked, every hiding place a giant serpent might have spent the daylight hours combed through, but nobody had found a single trace of the lamia. It was like she simply vanished into thin air each morning.

Originated from Greece. That brought up another interesting question: exactly how did a giant serpent with a human torso get all the way from Greece to New York? Popular theories ranged from being a stowaway on a cargo ship to through a portal by a careless warlock, but no one knew for sure.

Alec shut the book with a quiet sigh, and carefully set it down on the coffee table.

He glanced up at the television screen, just in time to see a group of scantily-clad mundane women in what seemed to be a rainforest of some sort, wriggling their butts at him. He blinked. Mundanes were so _weird_.

“Nothing?” From his prone position, Magnus cracked an eye open, and Alec mutely shook his head in response. Where in the name of Raziel could a snake of that size be hiding?

“ _– my anaconda don’t, my anaconda don’t, my anaconda don’t want none unless you got buns, hun,_ ” sang the woman on the television.

Alec jerked around so fast he nearly toppled into Magnus’ lap. “Anaconda!”

“Yeees, that’s the name of the song,” his boyfriend said slowly, in a rather bemused tone. A leer flitted across his face. “Why, how scandalous, Alexander. Propositioning me in the middle of the day?”

Alec shook his head, and didn’t even bother wasting the time to facepalm. “No, I mean, we’ve left no stone unturned in the whole of New York, and found no traces of the lamia. But what if she’s an _aquatic_ snake?”

Magnus sat up. He was wide awake now, cat-slit pupils fixed unblinkingly on Alec’s.

His face flushing from the close scrutiny, Alec broke eye contact first. “It’s just a thought,” he mumbled.

A piece of paper landed in his lap, the map of New York sketching itself out on the blank surface like in that movie Magnus once showed him, something about a self-updating map in a school of magic. Eight little dots winked into existence, the places where the children were last seen. Nobody had seen any correlation between all these locations – they were scattered all over, and didn’t seem to form any sort of regular shape – and it was eventually assumed that the victims were picked at random.

Alec’s finger landed on the body of water that meandered through the centre of the map, almost equidistant from the two most isolated cases.

“She’s in the Harlem River,” he breathed, fissures of electricity sizzling in his veins, and then – “I need to go.”

Magnus dropped a quick peck on his lips, resettling himself lengthwise on the couch now that Alec had vacated it. His pupils were fully dilated into round orbs, ringed in green flecks that glittered under the fading light of the setting sun, the way Church looked every time one of the children accidentally stepped on his tail. “Happy hunting.”

~*~*~*~*~

Alec paused at the foot of Broadway Bridge, fingering the fletching on his arrow in a nervous twitch he’d never quite managed to get rid of. He’d walked the length of the entire river twice already, but there was no sight of the lamia.

What if he’d been wrong? Just about everyone was studying the lamia’s movements, trying to track her. What if he was just jumping at shadows, seeing correlations that weren’t there? Every single female with any modicum of combat ability had volunteered for the patrols, or communications, or anything they could do to help. Right now, Izzy was probably out somewhere with Clary and Maia. Surely one of them would have found something by now, if there was really anything to find? It was already three hours after sunset. What if he was just wasting time, while the lamia was off attacking her ninth victim? She could be anywhere. She could –

Alec swung around, arrow already notched and ready to fire from sheer muscle memory alone. He could have sworn he’d just heard –

The light breeze rustled through the long reeds at the edge of the river, and belatedly Alec lowered his bow.

 _Get a grip, Lightwood_ , he chided himself as he continued walking, and was glad no one was around to witness his mortification, not even Magnus. He knew intellectually that his boyfriend wouldn’t judge him, not after four years of watching Alec trip over himself – case in point, having a knife thrown at his head because Alec was too out of it to realise who it was, as if anyone else would be in a High Warlock’s library – but old habits were hard to break.

He almost missed the faint splash of water.

Alec _stilled_.

A serpentine shape rose out of the ripples, slithering onto the bank with the barest whisper of scales against grass. Moonlight glanced off a humanoid figure, but her back was to him for the moment and she didn’t seem to have seen him.

He let the arrow fly.

The lamia screeched, an inhuman sound rasping from her throat, but he didn’t have the time to wonder how she’d managed to produce it at all. Despite her size, the lamia was _fast_ , her waist-length hair whipping across Alec’s face like a thousand razors when he tried to evade her initial lunge.

They circled each other warily, the lamia plucking the second arrow from her side – too fast, he’d been aiming for her heart, but he missed the shot when she lunged at him – and throwing it aside with a hiss. Her body swayed gently in an invisible breeze, naked breasts bouncing rhythmically, the only movement in this otherwise still palette.

His eyes trailed lower, down to the flat abdomen and the fine dusting of hair leading below her hips, as though she was wearing a scale-patterned skirt. Just like Magnus, she didn’t possess a belly button, but otherwise she looked almost exactly like a real human woman. When he looked up again, the breasts seemed to be swelling in size, until they filled his vision completely. Thick brown nubs crested the two firm mounds of flesh, and Alec thought fleetingly, eyes glazing over, _ah, this must be what a woman looks like when aroused._

Unfortunately for her, he wasn’t the slightest bit interested.

The lamia undulated her body yet again, thrusting her chest outwards, all the while creeping towards him agonising inch by inch. That was probably how she’d enthralled all those other males.

His thumb rested on the soothing coolness of his seraph blade, but Alec didn’t so much as twitch, not until the last moment when she was finally, _finally_ within striking range.

“Azrael!”

They struck at nearly the same time, Alec just a hairspan faster, ducking out of the way as her clawed fingers came slashing through the air. His own seraph blade bit deep into her left side, where his first arrow had struck her, and he felt the bones of her ribcage crunch under the impact. The lamia screeched again in pain, flailing backwards, her human features frozen in an expression of shock. Probably wondering why her thrall didn’t work on him.

Alec didn’t give her the chance to recover.

A step to the side, a leap over the tail that seemed to come out of nowhere, and this time Azrael embedded itself in her heart as Alec clung stubbornly onto her back. The lamia thrashed under his grip, but Alec could feel her struggles weakening, her life force draining out of her together with the blood soaking into the riverbank.

With a final rattling hiss, the lamia collapsed at his feet. Unlike the demons he was used to hunting, she didn’t dissolve. Alec absently wiped his sticky fingers on his pants, staring down at her.

He called Magnus, because that was a _thing_ people did, right? Call their significant other to tell them where they were going? At least, that was what all those mundanes on television did.

“I’m taking her to the Institute,” he explained.

“I’ll meet you there,” the warlock promised, and hung up.

~*~*~*~*~

The doors to the New York Institute swung open at his touch, as though someone had been expecting him. Maybe it was Magnus, knowing that Alec would have a bit of trouble carrying a giant serpent and trying to unlock the door simultaneously. His boyfriend was considerate like that.

His foot crossed over the threshold, and he paused.

There had to be over a hundred people crammed into the entrance hall, spilling down the sweeping stairs and leaning over the second floor balcony. Possibly the only thing that made Alec step into the Institute, the heavy doors clanging shut like a doomsday toll behind him, was the sight of Magnus leaning against the bannisters, grinning at him.

The silence was eerie as he slowly bent down, setting the human half in his arms on the floor and then unwound the thick coils of snake from where it looped over both shoulders and around his neck – the only way he could figure out how to carry three metres of serpent on top of half a woman. He’d never been so happy about Magnus’ penchant for mundane television. Apparently, mundane women hung large pink furred imitations of pythons around their necks as fashion accessories, which was where he had gotten the idea from.

Then the clapping started.

Alec’s eyes found Magnus as though magnetised, but his boyfriend was too busy looking over his form, as though checking for injuries. Nothing a quick _iratze_ couldn’t heal, Alec wanted to tell him, but the massive crowd froze his tongue.

His eyes caught a flash of Jace trying to squeeze down the packed stairs, Clary and Izzy close behind him, before his attention was pulled away. “How did you avoid being enthralled?” yelled someone he didn’t recognise. “Is there some secret Shadowhunter rune that prevents mind control?”

There wasn’t any, not to the best of Alec’s knowledge, even though there _were_ some runes – like the one Sebastian Verlac had used on Jace, so long ago – that could manipulate the mind. “Er,” he said intelligently. His eyes gravitated to Magnus again, and the warlock was still beaming widely, slowly making his way towards Alec.

Alec looked down briefly, steeling himself. He could do it – for Magnus, if not for himself. His boyfriend wasn’t a dirty little secret.

 _Nobody would care_ , he repeated the mantra to himself, and then opened his mouth.

“Because I’m gay.”

He did his best, not a single tremor to be heard in his voice, nothing to betray the sharp jackrabbiting of his heart, the knee-jerk torrent of fear and terror that washed over him. His family already knew, he reminded himself. They wouldn’t care. Homosexuality was no longer a crime; he wouldn’t have his runes stripped for this admission.

He felt an arm wrap around his waist, tugging him closer until his shoulders were pressed up against Magnus’, and it took conscious effort to relax his muscles, to resist the initial urge to pull away. If Magnus wanted to make a public statement, smirking at the man who’d asked that question, the warlock deserved it.

Alec dropped his eyes to the dead lamia on the floor, or else even Magnus’ arm wouldn’t be enough to keep him in place, at the centre of everyone’s attention. No one else would die because of her now. His shoulders loosened, the tension finally seeping out of them as his boyfriend expertly directed half the attention towards himself, sensing Alec’s discomfort with the general situation.

He’d done it.

“So, am I getting a new snakeskin belt for my birthday?” Magnus whispered.

**Author's Note:**

> Yes, Magnus summoned the entire crowd, because he was _damned_ proud of Alec and wanted everyone to know it.


End file.
